Rotary screw compressors of the type wherein a gas is introduced through an intake port into compressor rotors, and discharged through a discharge port in a compressed state are well known in the art. In these compressors, an inherent pressure differential exists between the intake or suction side and the outlet or discharge side of the compressor which tends to force the rotors to move toward the intake side In order to balance the rotors, it is known to utilize an oil pump or discharge pressure to provide hydraulic pressure acting on pistons located on the intake or suction side of the rotors which bias the rotors against the pressure differential. A problem with such compressors is that the balancing pressure on the pistons is not responsive to the various operating parameters other than outlet pressure of the rotary screw compressor
There is a need for a rotary screw compressor wherein the balancing pressure applied to the pistons is responsive to the various operating parameters thereof. This invention is directed to satisfying this need